Single Motor Multiple Pumps

ABSTRACT

A motorized pump assembly including a motor having a rotatable shaft, at least a first pump having a first impeller and a second pump having a second impeller, wherein the first pump and the second pump are connected to the motor through a rotatable shaft, and wherein the first impeller of the first pump is independently operable from the second impeller of the second pump. The first pump includes a first one-way bearing operatively driven by the rotatable shaft when the rotatable shaft is rotated in a first direction, while the second pump includes a second one-way bearing operatively driven by the rotatable shaft when the rotatable shaft is rotated in a second direction, wherein the second pump and the second one-way bearing are not operatively driven by the rotatable shaft when the rotatable shaft is rotated in the first direction, and wherein the first pump and the first one-way bearing are not operatively driven by the rotatable shaft when the rotatable shaft is rotated in the second direction. A method of dispensing multiple fluids is also described.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Patent Application Ser. No.61/273,489 filed on Aug. 5, 2009.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to motorized pumps and methods fordispensing fluids. Particularly, the present invention relates to amotorized pump assembly and fluid dispensing method having a singlemotor operating more than one pump.

BACKGROUND OF THE INVENTION

Pumps are used in many fluid pump systems and applications. Peristalticpumps, which function to move fluids through tubes in a pulse-likefashion, are well known. Pumps are very useful in many householdappliances, such as washing machines and dishwashers, for providingmultiple detergents, softeners and conditioners that are used in theseappliances. In addition, because of the use of multiple fluids atdifferent times in the washing cycle, multiple pumps are typicallyneeded to supply each separate fluid. Given the limited interior spacein these types of appliances for the internal mechanisms, it would be anadvantage, for example, to operate two pumps with a single motor,thereby eliminating the need for two motors to operate two pumps, whilemaintaining the ability to use multiple fluids in a single pumpassembly.

The assembly and method of the present invention provide the foregoingand other advantages.

SUMMARY OF THE INVENTION

Generally speaking, the motorized pump assembly includes a single motorthat operates at least two pumps. In present assembly, a single motoroperates a first pump when the motor rotates its output shaft in a firstdirection and operates a second pump when the motor rotates its outputshaft in a second direction. In this manner, only one of the possiblemultiple pumps operates at a time. Accordingly, a single motor can beused to selectively and alternatively operate at least two pumps. Thesingle motor dual pumps can be used for any desired application, such aspumping liquids, gels, solids and other materials. The present inventionalso pertains to related methods, including methods of operating pumpsand methods of dispensing substances.

In one aspect, motorized pump assembly includes a motor having arotatable shaft, a first pump having a first impeller, a second pumphaving a second impeller, wherein the first pump and second pump areconnected to one another and to the motor through the rotatable shaft,wherein the first impeller of the first pump is independently operablefrom the second impeller of the second pump.

In another aspect, the first pump further includes a first one-waybearing rotatable in first direction. In yet another aspect, the secondpump further includes a second one-way bearing rotatable in a seconddirection.

In another aspect, a motorized pump device includes a motor driving arotatable shaft, a first pump having a first one-way bearing andoperatively driven by the rotatable shaft when the rotatable shaft isrotated in a first direction, a second pump having a second one-waybearing and operatively driven by the rotatable shaft when the rotatableshaft is rotated in a second direction, wherein the second pump and thesecond one-way bearing are not operatively driven by the rotatable shaftwhen the rotatable shaft is rotated in the first direction, and whereinthe first pump and the first one-way bearing are not operatively drivenby the rotatable shaft when the rotatable shaft is rotated in the seconddirection.

In yet another aspect, a method of dispensing fluids A method fordispensing multiple fluids comprising the steps of coupling a reversiblemotor having a rotatable drive shaft to a first fluid pump via a firstone-way bearing, coupling the reversible motor having a rotatable driveshaft to a second fluid pump via a second one-way bearing, operating thereversible motor to turn the drive shaft in a first direction to therebyoperate the first fluid pump to dispense a first fluid, operating thereversible motor to turn the drive shaft in a second direction tothereby operate the second fluid pump to dispense a second fluid, andwherein the second one-way bearing prevents the second fluid pump fromoperating to dispense the second fluid when the drive shaft turns in thefirst direction and the first one-way bearing prevents the first pumpfrom operating to dispense the first fluid when the drive shaft turns inthe second direction.

In yet another aspect of the method, the operation of the motor to turnthe rotatable drive shaft alternates between the first direction and thesecond direction automatically.

These and other aspects of the invention may be understood more readilyfrom the following description and the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

For the purpose of facilitating an understanding of the subject mattersought to be protected, there are illustrated in the accompanyingdrawings embodiments thereof, from an inspection of which, whenconsidered in connection with the following description, the subjectmatter sought to be protected, its construction and operation, and manyof its advantages should be readily understood and appreciated.

FIG. 1 shows one embodiment of a motorized pump assembly.

FIG. 2 shows the motorized pump assembly of FIG. 1 with a cover removedfrom a first pump.

FIG. 3 shows the motorized pump assembly of FIG. 1 with the first pumpremoved and a cover removed from the second pump.

FIG. 4 is a side view of the motorized pump assembly of FIG. 1 withportions of the first and second pumps cut-away.

FIG. 5 shows the motorized pump assembly and the direction of flow offluids into the two pumps.

DETAILED DESCRIPTION OF THE INVENTION

While this invention is susceptible of embodiments in many differentforms, there is shown in the drawings and will herein be described indetail a preferred embodiment of the invention with the understandingthat the present disclosure is to be considered as an exemplification ofthe principles of the invention and is not intended to limit the broadaspect of the invention to embodiments illustrated.

Referring to FIG. 1-5, there is illustrated a motorized pump assembly10, having a motor 12, and at least two pumps, a first pump 14 and asecond pump 16. The motor 12 drives a rotatable shaft 18, which drivesthe pumps. The first pump 14 has a first impeller 20 and includes afirst cover 14 a. The second pump 16 has a second impeller 22 andincludes a second cover 16 a, the covers being used to enclose thetubing 14 b and 16 b running through the first and second pumps,creating separate pump cartridges. The pumps or pump cartridgescontaining the pumps and tubing for dispensing the fluids can beoptionally coupled together in a known manner, such as through bolts orscrews. In this manner, multiple pumps or pump cartridges can be joinedtogether, operating together using one motor 12. The pumps may be anysuitable kind, including peristaltic pumps, which move fluids throughtubes in a pulse-like fashion and are typically useful in fluid pumpsystems.

As shown FIGS. 2 and 3, each pump includes an impeller, specifically,the first pump 14 includes a first impeller 20, while the second pump 16includes a second impeller 22. In addition, the first impeller 20includes a first one-way bearing 24, while the second impeller 22includes a second one-way bearing 26. Each bearing 24, 26, and thus theimpellers are operatively driven by the rotatable shaft 18 when therotatable shaft is rotated in a first direction or a second direction.The impellers create the pulse or massaging action, which moves thefluid through the tubing.

In one embodiment, the first one-way bearing 24 can be adapted to rotatein a first direction, for example, in clockwise direction when the firstbearing 24 engages the motor shaft 18 when the motor shaft is rotatingclockwise. In this manner, the first pump 14 operates when the firstone-way bearing 24 engages the clockwise rotating motor shaft 18.However, the first pump 14 and the first one-way bearing 24 are notoperatively driven by the rotatable shaft 18 when the rotatable shaft isrotated in the second direction. When the motor shaft 18 rotates in asecond direction, counter-clockwise for example, the first one-waybearing 24 slips on the motor shaft and does not operate the first pump14.

The second pump 16 includes second one-way bearing 26, which operates ina second direction. Thus, the second one-way bearing 26 can be acounter-clockwise bearing that engages the motor shaft 18 only when themotor shaft is rotating in a counter-clockwise direction. The secondpump 16 operates only when the second one-way bearing 26 engages thecounter-clockwise rotating motor shaft. The second pump 16 and thesecond one-way bearing 26 are not operatively driven by the rotatableshaft when the rotatable shaft is rotated in the first direction. Whenthe motor shaft 18 rotates in the first direction or clockwise, thesecond one-way bearing 26 slips on the motor shaft and does not operatethe second pump 16.

Accordingly, only one pump is operated at a time by the motor 12depending on which direction the motor rotates its output motor shaft18. Depending on the direction of rotation of the shaft 18, either thefirst pump 14 operates to pump fluids, while the second pump 16 is held,or the second pump operates to pump fluids, while the first pump isheld. In this manner, the present device may be used to convey more thanone fluid into the desired system at independent intervals.

The direction of the motor rotation can be selected by reversing thepolarity of the DC current applied to the electric motor 12. Inaddition, it is understood that any type of suitable motor and pumps maybe used, and any mix of pumps may be utilized, such as two peristalticpumps of different capacities or two different sized gear pumps. Also,the speed of each pump may be controlled by an external electricalfrequency control unit (not shown).

As shown in FIG. 5, when the pump assembly 10 is in operation, the motor12 rotates in both a clockwise and a counterclockwise direction, whereinthe motor operates the two impellers 20 and 22, each impeller having itsown one-way bearings 24, 26 with a clockwise or counterclockwiserotation. When the motor 12 is rotating clockwise, the first pump 14 isactivated, thereby pumping fluid, such as a detergent into the machinesystem (not shown), while the second pump 16 is slipping and notfunctioning due to its one-way bearing 26. When the motor 12 is rotatingin a counterclockwise direction, the first pump 14 slips and ceases tofunction, while the second pump 16 is now activated thereby pumping asecond fluid, such as a fabric softener, into the machine system. Thereis no added torque on the motor 12 as it drives each pump separately,one at a time. In this manner, a single motor can operate numerous pumpsin one operation.

The motorized pump assembly 10 would be useful in a method fordispensing multiple fluids, for example, in a dishwashing machine wheredetergent and then a rinse aid are used. In one embodiment, the methodwould include coupling a reversible motor 12 having a rotatable driveshaft 18 to a first fluid pump 14 via a first one-way bearing 24, and toa second fluid pump 16 via a second one-way bearing 26. The reversiblemotor 12 would then turn the drive shaft 18 in a first direction tothereby operate the first fluid pump 14 to dispense a first fluid.Likewise, operating the reversible motor 12 to turn the drive shaft 18in a second direction would thereby operate the second fluid pump 16 todispense a second fluid. As previously described, the second one-waybearing 26 prevents the second fluid pump 16 from operating to dispensethe second fluid when the drive shaft turns in the first direction,while the first one-way bearing 24 prevents the first pump 14 fromoperating to dispense the first fluid when the drive shaft 18 turns inthe second direction. Accordingly, the method provides operation of atleast two pumps, for two separate fluids through the use of a singlemotor.

In addition, although the embodiment described has only two pumps drivenby a single motor, embodiments of the present invention could have morethan two pumps. For example, an embodiment could have more than oneclockwise operated pump and/or more than one counter-clockwise operatedpump. In addition, multiple pumps could be coupled or to one another orstacked together in a known manner for use in multiple machinesrequiring the pumping of different fluids.

The matter set forth in the foregoing description and accompanyingdrawings is offered by way of illustration only and not as a limitation.While particular embodiments have been shown and described, it will beapparent to those skilled in the art that changes and modifications maybe made without departing from the broader aspects ofapplicants'contribution. The actual scope of the protection sought isintended to be defined in the following claims when viewed in theirproper perspective based on the prior art.

1. A motorized pump assembly comprising: a motor having a rotatable shaft; a first pump having a first impeller; a second pump having a second impeller, wherein the first pump and second pump are connected to one another and to the motor through the rotatable shaft; and, wherein the first impeller of the first pump is independently operable from the second impeller of the second pump.
 2. The motorized pump assembly of claim 1, wherein the first pump further includes a first one-way bearing.
 3. The motorized pump assembly of claim 2, wherein the first bearing is rotatable in first direction.
 4. The motorized pump assembly of claim 3, wherein the first bearing is rotatable in a clockwise direction.
 5. The motorized pump assembly of claim 1, wherein the second pump further includes a second one-way bearing.
 6. The motorized pump assembly of claim 5, wherein the second bearing is rotatable in a second direction.
 7. The motorized pump assembly of claim 6, wherein the second bearing is rotatable in counterclockwise direction.
 8. A motorized pump device comprising: a motor driving a rotatable shaft; a first pump having a first one-way bearing and operatively driven by the rotatable shaft when the rotatable shaft is rotated in a first direction; and a second pump having a second one-way bearing and operatively driven by the rotatable shaft when the rotatable shaft is rotated in a second direction; wherein the second pump and the second one-way bearing are not operatively driven by the rotatable shaft when the rotatable shaft is rotated in the first direction; and wherein the first pump and the first one-way bearing are not operatively driven by the rotatable shaft when the rotatable shaft is rotated in the second direction.
 9. The motorized pump device of claim 8, wherein the first pump further includes a first impeller moveable through the first one-way bearing in the first direction.
 10. The motorized pump device of claim 8, wherein the second pump further includes a second impeller moveable through the second one-way bearing in the second direction.
 11. The motorized pump device of claim 8, wherein the first direction is clockwise.
 12. The motorized pump device of claim 8, wherein the second direction is counterclockwise.
 13. A motorized pump assembly comprising: a motor having a rotatable shaft; a first pump having a first impeller mounted on a first one-way bearing, the first impeller operatively driven by the rotatable shaft when the rotatable shaft is rotated in a first direction; a second pump having a second impeller mounted on a second one-way bearing and operatively driven by the rotatable shaft when the rotatable shaft is rotated in a second direction; and, wherein in the first direction the first pump operates, while the second pump holds, and in the second direction the second pump operates while the first pump holds.
 14. A method for dispensing multiple fluids, the method comprising the steps of: providing a motor having a rotatable shaft; providing a first pump having a first impeller mounted on a first one-way bearing, the first impeller operatively driven by the rotatable shaft when the rotatable shaft is rotated in a first direction; providing a second pump having a second impeller mounted on a second one-way bearing and operatively driven by the rotatable shaft when the rotatable shaft is rotated in a second direction; staying operation of the second pump when the rotatable shaft is rotated in the first direction; and staying operation of the first pump when the rotatable shaft is rotated in the second direction.
 15. A method for dispensing multiple fluids comprising the steps of: coupling a reversible motor having a rotatable drive shaft to a first fluid pump via a first one-way bearing; coupling the reversible motor having a rotatable drive shaft to a second fluid pump via a second one-way bearing; operating the reversible motor to turn the drive shaft in a first direction to thereby operate the first fluid pump to dispense a first fluid; operating the reversible motor to turn the drive shaft in a second direction to thereby operate the second fluid pump to dispense a second fluid; and wherein the second one-way bearing prevents the second fluid pump from operating to dispense the second fluid when the drive shaft turns in the first direction and the first one-way bearing prevents the first pump from operating to dispense the first fluid when the drive shaft turns in the second direction.
 16. The method of claim 15, wherein the operation of the motor to turn the rotatable drive shaft alternates between the first direction and the second direction automatically.
 17. The method of claim 15, wherein the first direction is a clockwise direction.
 18. The method of claim 15, wherein the second direction is a counterclockwise direction.
 19. A method for automatically dispensing multiple fluids comprising the steps of: pumping a first fluid via a first pump in response to the operation of a motor turning a rotatable drive shaft in a first direction; and pumping a second fluid via a second pump in response to the operation of the motor turning the rotatable drive shaft in a second direction.
 20. The method of claim 19, wherein the method further comprises the steps of: staying operation of the second pump when the rotatable shaft is rotated in the first direction; and, staying operation of the first pump when the rotatable shaft is rotated in the second direction. 